fjO MOEPHOLOGY AND EVOLUTION grasping organ. The hallux, on the contrary, makes the foot a powerful grasping organ. When the actions of the hand are closely watched, it is seen how the Chimpanzee employs the index and middle fingers together for most purposes. It will be seen later that the anatomical differences between the human and anthropoid hand are not sufficient to explain the enormous differences in function. The reasons are to be found in the complexity of the brain and in the main uses to which the hand is put. In Man the hand is not used as an aid to progression, or as a support for the body, but it has been set free so as to act as the servant of his highly organized brain. The thumb has developed considerably and exceeds that of any Ape in size and in function. The other parts of his hand have not undergone such striking transformations, however, as the thumb. It is frequently stated that the Chimpanzee is filthy in its habits, but many examples in captivity do not manifest this trait, nor any tendency to immoral behaviour. There appears to me to be no doubt that the Chimpanzee is the most intelligent of the Anthropoid Apes, but there are individual differences in the degree of intelligence. Sally, the famous Chimpanzee belonging to the Zoological Society, had a higher degree of intelligence than her successors. Young animals have a good memory for faces, and they will remember a person who has injured them.* Distribution,—Of all the Anthropoid Apes no single Accounts of the habits are contained in papers 303, 314, 334, 344, 344, 355. 359» 3$3, 367* 3^3. 3&9, 3p8, 399.